Modules containing microprocessors, memories, and a plug-and-socket connector are known. Such a module is offered, for example, under the name of PCMCIA (Personal Computer Memory Card International Association) and is described in more detail in Funkschau 2/1994, pp. 76-79 by Fereydun Khanide in xe2x80x9cGute Karten fxc3xcr die Zukunftxe2x80x9d (Good cards for the future).
Such modules are designed as additional PC cards thus allowing their application range to be expanded. For many applications it is necessary, or at least recommended, that such a module be personalized. This, however, requires a complex procedure that increases the cost.
Some conventional processor chip cards are being increasingly used as individual electronic encryption devices, for which they are also personalized. Due to their external dimensions and the type of their electrical contacts, these are the dominant media in this application field.
The following properties of chip cards are useful for this purpose:
1. standard external dimensions, mechanical properties, and interface,
2. compact storage (stackable),
3. simple transportation by the user,
4. (invisible when) carried on the user""s body,
5. numerous plug-in cycles in different terminals, and
6. cost-effective mechanical-electrical processing of large numbers in loading individual encryption means or other data during the card production process (hereinafter referred to as xe2x80x9cpersonalizingxe2x80x9d).
Processor chip cards have, however, a at least one shortcoming: due to the mechanical specifications of ISO Standard 7816 regarding their flexibility, thickness, and interface, the size of their semiconductor chip is limited to approximately 25 cm2. This limits the processor performance of the chip card, and makes it unsuitable for use in many applications, such as, for example, quick data encryption.
The PCMCIA module, for example, is an alternative to the chip card. It has the same external dimensions, except thickness, as a chip card. The thickness, for example, can be selected with enclosure type I or II (max. thickness=3.5 mm) so that a complete microprocessor architecture can be accommodated. The four-pole interface to the outside allows data transfer rates of up to 30 Mbit/s as opposed to approximately 10 kbit/s for the chip card.
Of the six aforementioned properties of the chip card, the PCMCIA module has the first five and is therefore an almost ideal alternative to the chip card.
The four-pole interface of the PCMCIA allows high processing rates in operation, but is a disadvantage from the following points of view:
a. increased mechanical wear due to complex plug-in contacts; therefore fewer plug-in cycles;
b. interface contact contamination hazard; thence the need for a protective case for transport on a person""s body;
c. complex mechanical guidance and contacting during the personalization process; therefore this step can only be automated at a high cost;
d. conventional chip card personalization systems cannot be used for PCMCIA modules as well.
A PCMCIA chip card, onto which an ISO chip card can be installed. The ISO chip card can be personalized and is designed so that it can exchange data with the PCMCIA chip card. For this purpose contacts are provided on both the PCMCIA chip card and the ISO chip card. Only when the personalized ISO chip card is installed on the PCMCIA chip card and is in contact with the latter can the PCMCIA chip card be accessed. A disadvantage of this card combination is that a separate personalized ISO chip card is needed in order to access the PCMCIA chip card.
An object of the present invention is to eliminate the above disadvantages of the module, in particular of the PCMCIA module.
The object can be achieved with a module having a chip card interface analogous to ISO 7816 ff. The chip card interface permits the module to be personalized.